Patents by Inventor Robert M. Schulz, Sr.

Robert M. Schulz, Sr. has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method of making a printed circuit board
    Patent number: 4325780
    Abstract: A printed circuit board is manufactured by preparing a dielectric substrate with copper-clad surfaces, applying an etch-resist layer in a positive image of the circuit trace, etching away the exposed, non-circuit copper surfacing, and thereafter removing the etch-resist material.
    Type: Grant
    Filed: September 16, 1980
    Date of Patent: April 20, 1982
    Inventor: Robert M. Schulz, Sr.